Electronic devices are now being used more and more frequently to monitor mechanical systems, for example to track the operation thereof.
In this line of thinking, devices are used to count the rotations of an object mobile about an axis, for example, such as a wheel of a vehicle, for example to track wear of the tire on that wheel.
A solution of this kind is described in PCT published patent application no. WO 2004/110793, for example.
In such electronic devices, the number of rotations of the object is stored in the form of counting information, for example in a memory of the device.
However practical it may be, the monitoring function of this solution (in particular. correct tracking of the mechanical system) is based on the accuracy of the stored counting information and is therefore vulnerable if there is any risk of that information becoming corrupted, for example by a fraudster attempting to reduce (or even to reset) the number of turns stored by the device.
French patent application no. FR 2 678 729 discloses an odometer for automobile vehicles with means for conditionally resetting it. In this document, the conditions for resetting are defined inside the device, and are therefore fixed, which rules out all flexibility of use.